A typical tandem-axle motor vehicle rear suspension will include right and left walking beams pivotally carried intermediate their front and rear ends on the vehicle frame, usually by means of leaf springs or the like. A pair of transverse axle housings is arranged to span the walking beams adjacent to their front and rear ends. Conventional connecting structure between the axle housings and walking beams includes, at each end of an axle housing, a pair of ears welded to the housing and spaced apart laterally so as to straddle the associated end of the walking beam. These ears are provided with circular openings coaxial with a transverse bore through the end of the walking beam and appropriate bushings and tie means are utilized to pivotally interconnect the housings and beams for relative movement about several transverse axes.
The basic problem encountered in systems of this type arises from the fact that the axle housing ears are seldom accurately positioned relative to the housing before welding and, if they are, the heat generated by the welding operation quite often distorts the relationship, with the end result that the suspension, when ultimately assembled, includes axle housings out of parallelism and one or the other or both housings are non-perpendicular to the fore-and-aft centerline of the vehicle. Substantial misalinement, distortion and other forms of inaccuracies lead to excessive wear on the vehicle tires, bearings and power train. Certain of these inaccuracies lend themselves to correction by cutting the offending ears off the housing and re-welding them. This type of correction is costly, time-consuming and more often than not fails to completely solve the problem.
According to the present invention, the suspension is improved by replacing each connection between walking beam and axle housing with a connection having provision for adjustment of the axle housings relative to each other and to the walking beam by simple adjusting means operative without re-welding or otherwise interchanging parts. The preferred form of the invention utilizes a pair of eccentrically related members which, when moved angularly relative to each other, create fore-and-after movement of that end of the axle housing previously determined to be out of line. Provision is made for effecting the adjustment by a simple tool, such as a wrench or the like. Tie means is provided for securing the adjustment after it is made. Further means is provided for easily releasing the parts for readjustment.
Further details of the invention and features and advantages thereof will become apparent to those skilled in the art as a preferred embodiment of the invention is set forth below.